United States Patent [19]
`Nishio et al.
`
`111111111111111111111111111111111111111111 1111111111 IIIII 111111 11111111 1111
`US005592332A
`[11] Patent Number:
`[45] Date of Patent:
`
`5,592,332
`Jan.7, 1997
`
`[54] RENTICULAR LENS, SURFACE LIGHT
`SOURCE, AND LIQUID CRYSTAL DISPLAY
`APPARATUS
`
`4,573,764
`4,730,897
`4,919,518
`
`3/1986 Bradley ................................... 348n86
`3/1988 McKechnie ............................. 359/452
`4/1990 Ogino ...................................... 359/457
`
`[75]
`
`Inventors: Toshikazu Nishio; Yoshiyuki
`Yamashita; Hiroyuki Amemiya;
`Michiko Takeuchi; Nobu Masubuchi,
`all of Tokyo, Japan
`
`[73] Assignee: Dai Nip]Jon Printing Co., Ltd., Japan
`
`[21] Appl. No.: 173,118
`
`[22] Filed:
`
`Dec. 27, 1993
`
`[30]
`
`Foreign Application Priority Data
`
`Dec. 25, 1992
`Apr. 16, 1993
`Jun. 16, 1993
`
`[JP]
`[JP]
`[JP]
`
`Japan .................................... 4-358319
`Japan .................................... 5-112397
`Japan .................................... 5-168376
`
`[51]
`
`Int. Cl.6
`
`........................... G02B 27/10; G02B 17/00;
`G03B 21/60
`[52] U.S. Cl . .......................... 359/619; 359/591; 359/621;
`359/455
`[58] Field of Search ..................................... 359/455, 456,
`359/615, 619, 591, 625, 639, 640, 707,
`620,621,622,626,627,628,454,459,
`592, 597
`
`Primary Examiner-Georgia Y. Epps
`Assistant Examiner-Ricky Mack
`Attorney, Agent, or Firm-Parkhurst, Wendel & Burr, L.L.P.
`
`[57]
`
`ABSTRACT
`
`A lenticular lens has a light transmitting substrate and a
`plurality of lens elements formed on the light transmitting
`substrate. The lens elements are defined in such a way that
`ridges thereof are aligned in parallel with each other,
`wherein 30°~810%~100° and R~20%, where 810% is a
`diffusing angle range with respect to normal of the one
`surface in the case that when light is entered from the
`opposite surface and transmitted from the one surface, the
`intensity of the light transmitted is equal to or more than
`10% of the intensity of the light transmitted in a peak
`direction of a main lobe; and R is the ratio of side lobes to
`main lobe. The intensity of side lobes which causes light loss
`and light stray can be remarkably reduced. Light can be
`equally and isotropically focused on in a predetermined
`diffusing angle range.
`
`[56]
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`4,432,010
`
`211984 Oguino .................................... 348n86
`
`62 Claims, 47 Drawing Sheets
`
`~94
`
`132
`
`~X
`
`y
`
`0
`
`TOYOTA EXHIBIT 1020
`
`Page 1 of 82
`
`

`

`U.S. Patent
`US. Patent
`
`Jan. 7, 1997
`Jan. 7, 1997
`
`Sheet 1 of 47
`Sheet 1 of 47
`
`’
`
`5,592,332
`5,592,332
`
`p
`
`y
`
`12
`
`10
`~
`
`F I G.
`
`
`
`F I G. 2
`
`Page 2 of 82
`
`Page 2 of 82
`
`

`

`U.S. Patent
`
`Jan.7, 1997
`
`Sheet 2 of 47
`
`5,592,332
`
`N
`
`L1 = L2
`
`FIG. 3
`
`N
`
`FIG. 4
`
`Page 3 of 82
`
`

`

`U.S. Patent
`
`Jan.7, 1997
`
`Sheet 3 of 47
`
`5,592,332
`
`/
`
`/
`
`Bro%
`
`/
`
`/
`
`/
`
`FIG. 5
`
`N (NORMAL)
`
`INTENSITY = I i ( 8)
`
`FIG. 6
`
`Page 4 of 82
`
`

`

`U.S. Patent
`US. Patent
`
`Jan. 7, 1997
`
`Sheet 4 of 47
`
`5,592,332
`5,592,332
`
`F I G. 7A
`
`10
`
`20
`
`FIG. 78
`FIG.7B
`
`MM '0
`10
`20
`mme‘ 20
`
`”MM '0v“mm 20
`
`20
`
`10
`
`75%
`
`F I G. SA
`FIG. 8A
`
`F I G. 88
`
`Page 5 of 82
`
`20
`
`10
`
`Page 5 of 82
`
`

`

`Jan. 7, 1997
`
`U.S. Patent
`~10
`20 '
`'
`'
`'
`'
`' .
`'
`
`5,592,332
`
`Sheet 5 of 47
`
`FIG. 9A
`
`~10
`/
`'
`"
`'
`'
`20'
`
`/
`
`/
`
`/
`
`FIG. 98
`
`~20'
`'
`'
`'
`/ ~10
`
`'
`
`/
`
`/
`
`/
`
`/
`
`/
`
`/
`
`/
`
`FIG. lOA
`
`/ ~20'
`/
`/
`/
`/
`/
`/
`10
`
`/
`
`/
`
`/ / / /
`
`FIG. lOB
`
`Page 6 of 82
`
`

`

`U.S. Patent
`
`Jan. 7, 1997
`
`Sheet 6 of 47
`
`5,592,332
`
`0
`0
`___ m_,o
`0
`
`0
`II
`
`II
`
`z
`0
`l-
`b3
`
`0::
`.0
`z
`<{
`~
`
`0
`0
`(.!)
`
`0
`0
`(.!)
`I
`
`i
`~Q;
`O<!;--
`o-
`
`t
`
`.
`(.9
`
`LL
`
`0
`----Jo 0
`0 m
`
`I
`
`1-:r:
`l.L<.!) o-_j
`1-o zw
`WI(cid:173)
`~I­w(cid:173)
`n::~
`-::J(j)
`UJZ
`<(<!
`wn::
`~~--
`
`Page 7 of 82
`
`

`

`N
`~
`~
`....
`N
`\0
`01
`....
`01
`
`:!:l
`s,
`......:t
`~
`~
`t:r'
`00
`
`......:t
`~
`~
`~
`"......:t
`
`~
`
`~ e. ~ = """""
`
`V'l •
`0 •
`
`100
`
`lga>
`
`I
`
`50
`l
`
`l
`
`~810%)
`
`70°(+2
`
`10 I'O
`8 0,.=140°
`
`<+2>zeH =74o
`
`37o 8H
`
`~~
`
`FIG. 12
`----DATA -,;;....
`
`ro ( 8)
`0
`
`I
`
`50
`I
`
`I
`
`100
`
`-90°1
`
`~ I i=O
`~8)
`INCIDENT ANGLE : i = 0
`
`30°
`
`I
`
`~ANgLE~
`
`~ ?-....
`
`8-[~J
`t
`
`MAIN DIRECTION = NORMAL DIRECTION
`
`70°
`
`(-2
`810%)
`
`-60°
`
`-37°
`2
`
`(-8H)
`
`TRANSMITTED LIGHT
`MEASUREMENT OF
`
`Page 8 of 82
`
`

`

`N
`~
`~
`....
`N
`\C
`Ul
`....
`Ul
`
`:!:l
`s,
`~
`t:r'
`00.
`
`00
`
`.....:J
`\C
`\C
`1-"
`".....:J
`
`~
`
`~ = ~
`
`~
`~
`•
`rJ1
`d •
`
`goo
`
`100
`
`I
`
`50
`I
`
`SIDE ROBE
`
`I ~t1
`
`0
`
`~ nn T IJ. ----( INTENSITY OF SIDE ROBES X 100 = 26%)
`
`FIG. 13
`
`R INTENSITY OF MAIN ROBE
`
`50
`I
`
`I
`
`100
`
`-90ol
`
`60°
`
`-60°
`
`8H
`
`0°
`3
`
`-f¢=0
`
`~ APEX ANGLE = 90°
`
`i = 0
`
`INCIDENT ANGLE :
`
`tY roc 8)
`
`~1i~ft-=82°
`Brooro
`20(8~!oj;7
`
`0
`
`8H=70
`
`4
`2
`
`340(-z
`
`810%-36°
`
`(--)
`
`2
`
`-42°
`
`~ANGLE~
`
`0
`
`8 [o]
`t
`
`MAIN DIRECTION = NORMAL DIRECTION
`
`(-2) -30°
`
`8H
`
`TRANSMITTED LIGHT
`MEASUREMENT OF
`
`Page 9 of 82
`
`

`

`N
`\C
`01
`-..
`01
`
`-.. w w
`
`N
`
`:!:l
`~
`\C
`~
`rJJ. =(cid:173)
`
`(C)
`
`......:.
`\C
`\C
`!-"'
`"......:.
`
`~
`
`~ ;-= ~
`
`~
`•
`rJl
`0 •
`
`!goo
`
`100
`
`I
`
`50
`~\ I
`
`~\...SIDE ROBE
`
`FIG. 14
`~ nATA ~ INTENSITY OF SIDE ROBES xi00-13%)
`
`R ( INTENSITY OF MAIN ROBE
`
`I
`
`50
`I
`
`I
`
`100
`
`-goo/
`
`36o(t BH)p HALF-VALUE ANGLE =73°
`
`4,o%=9oo
`
`45°(+ 27
`2
`
`810%)
`
`APEX ANGLE a = I 00
`
`0
`
`~ 10
`
`I
`
`I 300
`
`~ !0(8)
`
`INCIDENT ANGLE : i = 0
`
`0
`~
`ANGLE~
`8 [ 0]
`t
`
`MAIN DIRECTION = NORMAL DIRECTION
`
`-60°
`
`-45°
`-y>
`(
`B1oo' -37°
`
`(-BH 2) -30°
`
`TRANSMITTED LIGHT
`MEASUREMENT OF
`
`Page 10 of 82
`
`

`

`N
`t w
`• N cw
`~ ~
`c
`,.
`tit
`c
`
`.....:t
`~
`g,
`~ .....
`rJJ. =(cid:173) ro
`
`Q
`
`.....:t
`\C
`\C
`.....
`".....:t
`~
`
`~ = f""f"
`
`f""f"
`~
`~
`•
`
`L! • rJ).
`
`~=98°
`
`60°
`
`480(+80%)
`
`40° (t ~) ~HALF-VALUE ANGLE = 80 °
`
`~ oO
`
`I
`
`30o
`
`t;YI0(8)
`'8
`
`INCIDENT ANGLE : i = 0
`
`F I G. 15
`
`lgoo
`
`100
`
`I
`
`50
`I
`
`0 ~ ~1nr:-r:mc~::
`
`I ~~ I
`
`~ lll11l1 ~
`
`50
`I
`
`I
`
`100
`
`-9ool
`
`-60°
`
`50°
`
`(-8~o;") -40°
`(-BH)
`
`2
`
`-30°
`
`TRANSMITTED LIGHT ~ ANGLE~
`MEASUREMENT OF
`
`0
`
`8 [ o]
`t
`
`MAIN DIRECTION= NORMAL DIRECTION
`
`Page 11 of 82
`
`

`

`U.S. Patent
`
`Jan. 7, 1997
`
`Sheet 11 of 47
`
`5,592,332
`
`__ ____,
`
`0
`
`0 mo
`0
`
`\
`
`II
`
`z
`Q
`t;
`w
`a::
`0
`z
`<!
`~
`
`0
`0
`t()
`I
`
`0
`1.{)
`
`i
`
`0
`1.{)
`
`LL
`
`0
`0
`<.0
`I
`
`0
`___ o_jO
`o(cid:173)
`m
`I
`
`Page 12 of 82
`
`

`

`N
`\C
`Ol
`-..
`Ol
`
`-.. w w
`
`N
`
`:!:i
`s,
`N
`~
`
`~
`rJJ. =(cid:173)
`I'D
`
`"'-l
`\C
`\C
`~
`
`~ ?
`
`_."'-l
`
`·~ = ~
`
`~
`~
`~
`•
`rJ'J.
`d •
`
`lgoo
`
`100
`
`I
`
`50
`I
`
`I --~~~ l
`
`0
`
`F I G. 17
`
`130(8)
`
`~DATA -
`
`50
`I
`
`I
`
`100
`
`-gaol
`
`60°
`
`-60°
`
`i = 0
`
`•r I30( 8 >
`INCIDENT ANGLE:
`
`8" I
`
`I
`
`~ANGLE~
`
`0
`
`8 [o]
`t
`
`MAIN DIRECTION = NORMAL DIRECTION
`
`-30°
`
`TRANSMITTED LIGHT
`MEASUREMENT OF ·
`
`Page 13 of 82
`
`

`

`U.S. Patent
`US. Patent
`
`Jan. 7, 1997
`Jan. 7, 1997
`
`Sheet 13 of 47
`Sheet 13 of 47
`
`5,592,332
`5,592,332
`
`t
`
`t
`
`t
`
`10
`20
`
`/30
`
`4=
`
`
`
`=i3
`
`\
`32
`
`31
`
`F I G. 18
`
`Page 14 of 82
`
`Page 14 of 82
`
`

`

`U.S. Patent
`
`Jan.7, 1997
`
`Sheet 14 of 47
`
`5,592,332
`
`FIG. 19A
`
`I~ (8)
`
`-goo
`
`FIG. 19 B
`
`FIG. 19C
`
`Page 15 of 82
`
`

`

`U.S. Patent
`US. Patent
`
`Jan. 7, 1997
`Jan.7, 1997
`
`Sheet 15 of 47
`Sheet 15 of 47
`
`5,592,332
`5,592,332
`
`<(
`0
`N
`•
`
`-L
`
`L
`
`FIG.20
`
`0
`N
`•
`
`LL
`
`~I
`
`Page 16 of 82
`
`Page 16 of 82
`
`

`

`U.S. Patent
`
`Jan.7, 1997
`
`Sheet 16 of 47
`
`5,592,332
`
`42
`
`NORMAL
`
`43 ~~r-T-~~~-r-7~
`_::@
`
`c~/
`
`42'
`43
`
`,
`
`~~~~~~~~~
`
`0 ° ( NORMAL DIRECTION)
`
`FIG. 218
`
`F I G. 21C
`
`Fl G. 210
`
`Page 17 of 82
`
`

`

`U.S. Patent
`
`Jan. 7, 1997
`
`Sheet 17 of 47
`
`5,592,332
`
`+63°
`
`/
`
`/
`
`/
`
`/
`
`/
`
`/
`
`1 i ( 8)
`
`F I G. 22A
`
`8 =0°
`
`B
`
`8=-90°
`
`A
`
`8 =+90°
`
`FIG. 228
`
`B'
`'--
`
`MAIN ROBE
`
`SIDE ROBE
`
`FIG. 22C
`
`Page 18 of 82
`
`

`

`U.S. Patent
`
`Jan. 7, 1997
`
`Sheet 18 of 47
`
`5,592,332
`
`F I G. 23A =41 428
`
`FIG. 238
`
`FIG. 23C
`
`43
`
`6W~ij0i2J=:~A"
`
`0
`
`0
`
`0
`
`43
`
`FIG. 230
`
`0 0
`0 0
`0
`
`0
`
`FIG. 23E
`
`42A"
`
`Page 19 of 82
`
`

`

`U.S. Patent
`
`Jan.7, 1997
`
`Sheet 19 of 47
`
`5,592,332
`
`(XXlV 8)
`l
`
`FIG. 24A
`
`52
`
`IE p
`
`"1
`51~Jo
`
`xO
`
`53
`
`FIG. 248
`
`~-
`
`52
`
`50'
`
`FIG. 25
`
`Page 20 of 82
`
`

`

`U.S. Patent
`
`Jan. 7, 1997
`,...-------,
`//
`1 52 o
`
`Sheet 20 of 47
`
`5,592,332
`
`52a
`
`',
`'
`I
`
`......
`
`/
`
`r2
`
`X
`
`FIG. 26A
`
`52
`
`52b
`~
`
`FIG. 268
`
`52 a
`~
`
`FIG. 26C
`
`Page 21 of 82
`
`

`

`U.S. Patent
`
`Jan.7, 1997
`
`Sheet 21 of 47
`
`5,592,332
`
`R6
`
`R5
`
`R?
`
`R3
`
`R9
`
`R8
`Rll
`
`50
`
`R RAY
`
`IL
`j10°
`INCIDENT RAYS~ l
`REFRACTIVE
`\. NORMAL N ON
`/
`FLAT SURFACE
`~
`
`X
`
`REFRACTIVE INDEX n 1 = 1.5
`
`INDEX n2 = 1.0
`
`13
`
`1
`
`F I G. 27
`
`Page 22 of 82
`
`

`

`U.S. Patent
`
`Jan.7, 1997
`
`Sheet 22 of 47
`
`5,592,332
`
`y
`
`R4
`
`+r
`-r
`+x
`------~+-------------+------,----~~--------~x
`MEDIUM 2
`\
`\
`\
`\
`
`n2 = 1
`
`MEDIUM i
`
`\
`
`\
`
`'\
`
`'\ " "
`~n 1 =1.5 "
`
`I
`
`FIG. 28
`
`Page 23 of 82
`
`

`

`U.S. Patent
`
`Jan.7, 1997
`
`Sheet 23 of 47
`
`5,592,332
`
`y
`
`R9.5
`
`--~----~--------------~-------------.----~~~--~-x
`/ '
`
`/
`
`/
`
`/
`
`/
`
`/
`
`/
`
`/
`
`/
`
`/
`
`/
`
`/
`
`/
`
`/
`/
`NORMAL
`
`" " " " " " " "
`
`-rsin8c
`
`"
`
`'
`NORMAL
`
`R9.5
`
`F I G. 29
`
`Page 24 of 82
`
`

`

`U.S. Patent
`US. Patent
`
`Jan. 7, 1997
`Jan. 7, 1997
`
`Sheet 24 of 47
`Sheet 24 of 47
`
`5,592,332
`5,592,332
`
`I
`
`Mv
`
`‘v
`1’ V'
`v"‘V
`Amm
`
`FIG. 30
`FIG. 30
`
`Page 25 of 82
`
`

`

`US. Patent
`U.S. Patent
`
`Jan. 7, 1997
`Jan. 7, 1997
`
`Sheet 25 of 47
`Sheet 25 of 47
`
`5,592,332
`
`0
`(J)
`
`.........
`
`0 -CD
`T.vmmjozq
`
`w
`...J
`<.? z
`
`0
`~
`<(
`
` ASH35.35NEH/jg:>F_mzm._.z_
`
`w > s w
`
`cr::
`..........
`>-r-
`(f) z .........
`wCD
`r--
`~ZH
`8o
`0
`
`Page 26 of 82
`
`Sad
`
`w
`3
`g
`
`
`
`
`
`0
`1'--
`
`0
`(()
`
`0
`1.0
`
`-r
`
`.m.o_n_
`
`<>
`•
`(.!) -
`lL.
`
`0
`['()
`
`0
`N
`
`0
`
`0
`
`0 -I
`0
`N
`I
`0
`1'0
`I
`0
`~
`I
`0
`1.0
`I
`0
`({)
`I
`
`R I
`
`0
`(J)
`I
`
`Page 26 of 82
`
`

`

`U.S. Patent
`
`Jan. 7, 1997
`
`Sheet 26 of 47
`
`5,592,332
`
`FIG. 32A
`
`FIG.32B
`
`50
`
`60
`
`50
`
`60
`
`FIG.33A /
`
`/
`
`'
`
`/
`
`'
`
`/
`
`'
`
`'
`60' 50
`
`'
`
`'
`
`Fl G.33B
`
`Page 27 of 82
`
`

`

`U.S. Patent
`US. Patent
`
`Jan. 7, 1997
`Jan.7, 1997
`
`Sheet 27 of 47
`Sheet 27 of 47
`
`5,592,332
`5,592,332
`
`50
`
`60
`
`
`
`71
`
`FIG . 34
`FIG.34
`
`Page 28 of 82
`
`Page 28 of 82
`
`

`

`U.S. Patent
`US. Patent
`
`Jan. 7, 1997
`Jan. 7, 1997
`
`Sheet 28 of 47
`Sheet 28 of 47
`
`5,592,332
`5,592,332
`
`-
`
`lO co
`
`Ln
`N")
`
`u..
`
`
`
`(()
`Ln
`N')
`
`•
`
`(!J -u..
`
`Page 29 of 82
`
`Page 29 of 82
`
`

`

`U.S. Patent
`
`Jan.7, 1997
`
`Sheet 29 of 47
`
`5,592,332
`
`Bla
`
`:
`
`81
`
`FIG.36A ~~_Js2
`/'-J
`
`83
`
`jc
`
`Fl G.368
`
`F IG.36C
`
`Page 30 of 82
`
`

`

`U.S. Patent
`
`Jan. 7, 1997
`
`Sheet 30 of 47
`
`145
`\
`
`5,592,332
`
`96
`~99,}
`98 J40
`~99
`
`92
`
`F I G .3 7
`
`1
`I
`;~-, 1
`y
`I
`' ,,_,'
`
`-
`
`-
`
`-
`
`-
`
`-
`
`I
`- - - _;
`
`FIG.38
`
`140
`
`I
`I
`!_.-, I
`:
`y
`f', -~'
`\
`I
`'
`\L -
`
`- -
`
`-
`
`Page 31 of 82
`
`

`

`U.S. Patent
`
`Jan. 7, 1997
`
`Sheet 31 of 47
`
`5,592,332
`
`94
`F I G.39A \
`
`FIG. 398
`
`I
`I
`I
`-a I
`I
`__ ..j_ _____ _
`01
`I
`
`I
`\
`
`97
`
`97
`
`134
`
`Page 32 of 82
`
`

`

`U.S. Patent
`
`Jan. 7, 1997
`
`Sheet 32 of 47
`
`5,592,332
`
`FIG.39C
`
`I
`I
`+a
`-a'
`I
`-- '---f--- 1
`--;
`j->
`I X
`01
`I
`
`-----------~-----~-_j ........___... j ___ ___,
`
`131
`
`\
`
`"
`......
`
`I
`
`/
`
`/
`
`I
`I
`-r.=-b
`I
`
`/
`
`FIG. 390
`
`y
`t+b
`"'-r ..... ,
`I
`'
`
`\
`
`/
`
`/
`
`\
`\
`10
`1 ta
`I - - -~ -
`-:>X
`
`-
`
`131
`
`Page 33 of 82
`
`

`

`U.S. Patent
`
`Jan. 7, 1997
`
`Sheet 33 of 47
`
`5,592,332
`
`F I G . 40A
`
`\
`
`\
`
`"
`
`......
`
`I
`
`/
`
`/
`. /
`
`FIG.40B
`
`Page 34 of 82
`
`

`

`U.S. Patent
`
`Jan.7, 1997
`
`Sheet 34 of 47
`
`5,592,332
`
`I
`I
`I
`I
`\
`\
`
`' '
`
`I
`I
`I
`
`I
`
`/
`
`/
`
`/
`
`'
`
`I
`\
`\ IF
`\,.....
`/
`I \
`'./ )/
`I' I
`I /
`I ;
`
`FIG.41A
`
`I
`
`I
`
`I
`I
`I
`I
`\
`\
`
`I
`\
`I
`I
`I
`I
`I
`
`/
`
`/
`
`/
`
`FIG
`
`Page 35 of 82
`
`

`

`U.S. Patent
`
`Jan. 7, 1997
`
`Sheet 35 of 47
`
`5,592,332
`
`~94
`
`13 2 L......-,.-------..,.---..---....--__J/
`
`94----
`
`y
`
`0
`
`FIG.42A
`
`132
`
`132
`
`y
`
`0
`
`FIG.428
`
`Page 36 of 82
`
`

`

`U.S. Patent
`
`Jan.7, 1997
`
`Sheet 36 of 47
`
`5,592,332
`
`FIG.43
`
`100 97
`FIG. 44
`
`FIG. 45
`
`Page 37 of 82
`
`

`

`U.S. Patent
`
`Jan.7, 1997
`
`Sheet 37 of 47
`
`5,592,332
`
`FIG. 46
`
`L2s
`
`FIG.47
`
`Page 38 of 82
`
`

`

`U.S. Patent
`US. Patent
`
`Jan. 7, 1997
`Jan. 7, 1997
`
`Sheet 38 of 47
`Sheet 38 of 47
`
`5,592,332
`5,592,332
`
`1
`
`100
`
`91
`
`/
`
`/
`
`F I G . 48
`
`9 I
`
`
`94
`
`.t.X < X
`
`91
`
`97
`
`100
`
`--99
`
`FIG.49
`FlG.49
`
`
`
`n2 ~ n 1
`B>Bc
`
`91
`
`F I G . 50
`
`Page 39 of 82
`
`Page 39 of 82
`
`

`

`U.S. Patent
`
`Jan.7, 1997
`
`Sheet 39 of 47
`
`5,592,332
`
`vll3
`107
`
`~113
`
`110
`
`t
`
`112
`
`Ill
`
`FIG. 51
`
`Page 40 of 82
`
`

`

`U.S. Patent
`
`Jan. 7, 1997
`
`Sheet 40 of 47
`
`5,592,332
`
`0
`<D
`
`0
`0
`['-
`II
`I
`
`~
`
`t~~
`~~
`~~ ill]
`
`Cl)
`
`z
`0
`b w
`a:::
`0
`_j
`<l:
`::2:
`a:::
`0
`z
`z
`0
`b
`w
`a:::
`0
`z
`<l:
`::2:
`
`II
`
`w
`..-,__]
`...,..___ ~(.90
`cnz
`<t
`
`I
`
`\
`
`1-
`LLI
`o<.9
`_j
`l-0 zw
`WI-
`~~---
`W-
`0:::~
`::J(f)
`(J)z
`<(<!
`Wo:::
`~~---
`
`00
`\0
`I
`
`0
`0
`(J)O
`0
`
`0
`lO
`
`t
`~~
`o<t ~
`o-
`~
`
`N
`L()
`
`(!)
`
`LL
`
`0
`LO
`
`0
`00
`(J)
`I
`
`Page 41 of 82
`
`

`

`U.S. Patent
`
`Jan. 7, 1997
`
`Sheet 41 of 47
`
`5,592,332
`
`II
`
`~
`~
`
`0
`
`,....
`Q) @
`......
`~1
`
`1
`
`\
`
`z
`0
`I-
`(.)
`w
`0:::
`0
`
`II
`
`z
`0
`I-
`h3
`0::
`0
`z
`<I:
`~
`
`I-
`0
`0
`LLI
`"?
`0(9
`<.0
`_J
`1-o ~~
`zw
`WI-
`~~--
`W-
`0::2
`-:::J(J)
`(J)z
`<!<{
`Wet:
`21-
`
`~
`
`I
`
`0
`0
`mo
`0
`
`_......
`~
`tO
`C\1
`II
`0
`0
`X
`
`(f) w w CD
`!D 0
`~ 0:::
`z
`~ <t
`en
`~
`LL. LL.
`0 0
`>- >-
`I- I-
`C1) CJ)
`z z
`w w
`I- I-
`z z
`
`--
`t
`
`r0
`l{) .
`(.!)
`-
`LL.
`
`t
`
`0
`LO
`
`0
`0
`
`0
`0
`(j)
`I
`
`0
`0
`<.0
`I
`
`Page 42 of 82
`
`

`

`U.S. Patent
`US. Patent
`
`Jan. 7, 1997
`Jan. 7, 1997
`
`Sheet 42 of 47
`Sheet 42 of 47
`
`5,592,332
`5,592,332
`
`w
`.....J
`(.!) z
`<!
`w
`3
`g
`I
`LL
`.....J
`<! :r:
`t
`~N
`+ /'\t
`........
`
`0
`("()
`
`0
`CJ)O
`~-----, 0
`
`O
`0
`0
`<.0
`
`8‘
`
`w
`m
`0 a::
`w
`0
`(f)
`
`0
`1.0
`
`t
`
`0
`1.0
`
`•
`
`LL
`
`I“>IV!
`oom@Em:%<r\
`Qfi-vv59gm»
`
`FIG:chrtimz<mh
`
`
`
`
`
`Am:m"295meézmozu295me2:32
`
`VE_e
`
`LOkzmémmamdflE
`
`Page 43 of 82
`
`~(\J \
`
`I
`
`-
`
`0
`"'-._ (\J
`'\t
`
`0
`<.0
`
`Page 43 of 82
`
`
`
`
`

`

`5,592,332
`
`0
`0
`0'>0
`0
`
`0
`I{)
`
`t
`
`t
`
`1.{)
`L()
`
`(!)
`
`LL
`
`U.S. Patent
`
`Jan. 7, 1997
`
`Sheet 43 of 47
`
`-
`~
`0
`0
`+ -
`~
`'~Jo
`crf
`1'-
`
`ct:>N
`
`-
`-
`
`ct:>
`.........
`
`11
`
`f5
`~
`0
`w
`0::
`0
`_J
`<l:
`w
`~
`0::
`l'l_j
`0
`z ~L<DO
`ct:>Z
`<t
`z
`0
`~
`0
`w
`0::
`0
`z
`<l:
`~
`
`I
`
`\
`
`I-
`LLI
`ot9
`_j
`1-0
`zw
`WI-
`~I-W-
`n::~
`-:::1(!)
`(f)z
`<(<(
`Wn:::
`~I-
`
`0
`0
`(.()
`
`0
`
`II
`
`~
`~
`~N
`+
`0 -
`l'-
`1'0
`
`0
`0
`1'0
`
`0
`1'0
`I
`
`0
`
`~I'-
`1'0
`I
`
`CJ::)
`
`I
`
`00
`(.()
`I
`
`I ........
`
`Page 44 of 82
`
`

`

`U.S. Patent
`
`Jan. 7, 1997
`
`Sheet 44 of 47
`
`5,592,332
`
`I( 8)
`
`I (8)
`
`LcoNv
`
`0
`FIG.56D
`
`90
`
`FIG.56C
`
`Page 45 of 82
`
`

`

`U.S. Patent
`
`Jan. 7, 1997
`
`Sheet 45 of 47
`
`5,592,332
`
`b=O. 115mm
`a =0. 064mm
`PITCH =0. 0 SOm m
`CUTTING DEPTH =0. 0 25mm
`CUTTING DEPTH I _
`LENGTH OF LONGER AXIS - O ·
`
`I 0 B
`
`FIG. 57A
`
`Page 46 of 82
`
`

`

`U.S. Patent
`
`Jan. 7, 1997
`
`Sheet 46 of 47
`
`5,592,332
`
`b=0.115mm
`a =0. 064mm
`PITCH = 0.
`I 2 6m m
`CUTTING DEPTH :::::0. 0 9 4 7 mm
`CUTTING DEPTH I = 0 . 4 1 1
`LENGTH OF LONGER AXIS
`
`FIG.578
`
`Page 47 of 82
`
`

`

`U.S. Patent
`
`Jan. 7, 1997
`
`Sheet 47 of 47
`
`5,592,332
`
`_.,
`
`$N
`
`Cl,)
`
`(--, ~
`~~
`~-~rno
`
`0
`0
`1'-
`
`0
`0
`({)
`
`0
`0
`<.D
`
`0
`
`0 cno
`0
`
`0
`L()
`
`t co
`L()
`c:::r-
`O!- CD l9
`c:::r-
`o-
`t -
`
`LL
`
`0
`L()
`
`0
`0
`
`0
`
`0 en
`
`I
`
`z
`0
`1-
`0
`w n::
`
`0
`_j
`<(
`
`II
`
`I
`
`\
`
`w
`~ n::
`,.--,_J
`0 ~L<..90
`z
`CDZ
`<t
`z
`0
`b
`w n::
`0
`z
`<(
`~
`
`0
`
`0
`r0
`lo
`tD
`~ r0
`
`JIN I
`-
`
`I
`
`1-
`LLI
`0<..9
`1-...J
`
`zo ww
`21-
`wl-
`0::2
`-:::>(f)
`(f)z
`<l:<t
`wcr::
`~I-
`
`Page 48 of 82
`
`

`

`5,592,332
`
`1
`RENTICULAR LENS, SURFACE LIGHT
`SOURCE, AND LIQUID CRYSTAL DISPLAY
`APPARATUS
`
`BACKGROUND OF THE INVENTION
`
`5
`
`2
`wherein 30° ~010%~ 100° and R~20%, where 8 10% is a
`diffusing angle range with respect to normal of the one
`surface in the case that when light is entered from the
`opposite surface or one surface and transmitted from the one
`surface or opposite surface, the intensity of the light trans(cid:173)
`mitted is equal to or more than 10% of the intensity of the
`light transmitted in a peak direction of a main lobe; and R
`is the ratio of side lobes to main lobe.
`According to the present invention, the intensity of side
`lobes which causes light loss and light stray (light noise) can
`be remarkably reduced. In addition, light can be equally and
`isotopically focused in a predetermined diffusing angle
`range (30° ~ 810% ~ 100°).
`Thus, when the lenticular lens according to the present
`invention is used as a surface light source, bright surface
`light can be obtained without the need to increase the power
`consumption and heat generation. In addition, the light
`diffusing angle range and the equality and isotopic charac(cid:173)
`teristics of light intensity thereof is almost the same as those
`20 of the related art references.
`These and other objects, features and advantages of the
`present invention will become more apparent in light ofthe
`following detailed description of a best mode embodiment
`thereof, as illustrated in the accompanying drawings.
`
`10
`
`15
`
`BRIEF DESCRIPTION OF DRAWINGS
`
`1. Field of the Invention
`The present invention relates to a lenticular lens having a
`large number of lens elements defined so that their ridges are
`aligned in parallel with each other. The present invention
`also relates to a surface light source having the lenticular
`lens, and a liquid crystal display apparatus having the
`surface, light source as a back-light thereof.
`2. Information of the Related Art
`As disclosed in Japanese Patent Laid-Open Publication
`No. 2-284102 and 63-318003, and Japanese Utility Model
`Laid-Open Publication No. 3-92601, and the like, liquid
`crystal display apparatuses having a back-light type diffus(cid:173)
`ing surface light source or edge-light type diffusing surface
`light source are known. Such surface light sources have ·a
`lenticular lens formed of a large number of triangular prism
`shaped lens elements which are defined in such a way that
`their edges are aligned in parallel. The lenticular lens equally
`and isotopically diffuses emitted light in a desired angle 25
`range.
`When a lenticular lens is used along with a delustered
`transparent diffusing plate (delustered transparent sheet),
`light energy of the light source is more sharply distributed in
`a predetermined angle range than when the delustered
`transparent diffusing plate is used alone. In addition, the
`light is equally and isotopically diffused in the predeter(cid:173)
`mined angle range.
`However, since the vertical angles o; of the lens elements
`of the lenticular lenses are 60° or 90°, a part of rays of light
`deviate from the predetermined angle range. In other words,
`side lobes take place in an angle distribution of the intensity
`of transmitted light.
`Thus, such lenticular lenses are not suitable for liquid 40
`crystal display apparatuses. Although the lenticular lenses
`have an advantage of low power consumption, they display
`clear images especially in color with difficulty.
`If the output of the light source were increased so as to
`solve such a problem, the temperature of the liquid crystal
`device would adversely rise. The light which leaks out of the
`predetermined angle range would become noise (stray light),
`which would disturb the viewing of the user.
`
`35
`
`45
`
`FIG. 1 is a perspective view showing a first embodiment
`30 of a lenticular lens according to a first invention;
`FIG. 2 is a perspective view showing a second embodi(cid:173)
`ment of the lenticular lens according to the first invention;
`FIG. 3 is a schematic diagram for explaining a vertical
`angle of lens elements of the lenticular lens according to an
`embodiment of the first invention;
`FIG. 4 is a schematic diagram for explaining a vertical
`angle of lens elements of the lenticular lens according to an
`embodiment of the first invention;
`FIG. 5 is a schematic diagram for explaining a diffusing
`angle;
`FIG. 6 is a schematic diagram for explaining the intensity
`of transmitted light 1;(8);
`FIG. 7 A is a sectional view showing a composition of a
`lenticular lens and a light isotopic diffusing layer;
`FIG. 7B is a sectional view showing a composition of a
`lenticular lens and a light isotopic diffusing layer;
`FIG. SA is a sectional view showing a composition of a
`lenticular lens and a light isotopic diffusing layer;
`FIG. 8B is a sectional view showing a composition of a
`lenticular lens and a light isotopic diffusing layer;
`FIG. 9A is a sectional view showing a composition of a
`lenticular lens and a light isotopic diffusing layer;
`FIG. 9B is a sectional view showing a composition of a
`lenticular lens and a light isotopic diffusing layer;
`FIG. lOA is a sectional view showing a composition of a
`lenticular lens and a light isotopic diffusing layer;
`FIG. lOB is a sectional view showing a composition of a
`lenticular lens and a light isotopic diffusing layer;
`FIG. 11 is a schematic diagram showing a measurement
`result of transmitted light (for a lenticular lens with a vertical
`angle of 90°);
`FIG. 12 is a schematic diagram showing a measurement
`result of transmitted light (for a light isotopic diffusing
`layer);
`
`SUMMARY OF THE INVENTION
`
`50
`
`An object of the present invention is to provide a lenticu-
`lar lens for equally focusing light in a predetermined angle
`range without the need to increase power consumption and
`heat generation so as to emit bright surface light. Another 55
`object of the present invention is to provide a surface light
`source having the lenticular lens, and a liquid crystal display
`apparatus having the surface light source.
`According to the present invention, there is provided a
`lenticular lens, comprising:
`a light transmitting substrate having one surface and
`opposite surface; and
`a plurality of lens elements elongated on the one surface
`of said light transmitting substrate, having concave or con- 65
`vex shaped cross-sections, and defined in such a way that
`ridges thereof are aligned in parallel with each other,
`
`60
`
`Page 49 of 82
`
`

`

`5,592,332
`
`20
`
`25
`
`30
`
`35
`
`3
`FIG. 13 is a schematic diagram showing a measurement
`result of transmitted light (for a composition of a lenticular
`lens with a vertical angle of 90° and a light isotopic diffusing
`layer);
`FIG. 14 is a schematic diagram showing a measurement
`result of transmitted light (for a composition of a lenticular
`lens with a vertical angle of 100° and a light isotopic
`diffusing layer);
`FIG. 15 is a schematic diagram showing a measurement
`result of transmitted light (for a composition of a lenticular
`lens with a vertical angle of 110° and a light isotopic
`diffusing layer);
`FIG. 16 is a schematic diagram showing a measurement
`result of transmitted light (for an incident angle of 63°);
`FIG. 17 is a schematic diagram showing a measurement 15
`result of transmitted light (for an incident angle of 30°);
`FIG. 18 is a sectional view showing a first embodiment of
`a light source (back-light type) according to the first inven(cid:173)
`tion;
`FIG. 19A is a schematic diagram for explaining the
`intensity of transmitted light of the embodiment of FIG. 18;
`FIG. 19B is a schematic diagram for explaining the
`intensity of transmitted light of the embodiment of FIG. 18;
`FIG. 19C is a schematic diagram for explaining the
`intensity of transmitted light of the embodiment of FIG. 18;
`FIG. 20 is a sectional view showing a second embodiment
`(edge-light type) of the light source according to the first
`invention;
`FIG. 20A is a detailed drawing of the lenticular lens of the
`light source of FIG. 20;
`FIG. 21A is a sectional view for explaining the charac(cid:173)
`teristics of a light guiding plate;
`FIG. 21B is a sectional view for explaining the charac(cid:173)
`teristics of a light guiding plate;
`FIG. 21C is a sectional view for explaining the charac(cid:173)
`teristics of a light guiding plate;
`FIG. 21D is a sectional view for explaining the charac(cid:173)
`teristics of a light guiding plate;
`FIG. 22A is a schematic diagram for explaining the
`intensity of transmitted light of the embodiment of FIG. 20;
`FIG. 22B is a schematic diagram for explaining the
`intensity of transmitted light of the embodiment of FIG. 20;
`FIG. 22C is a schematic diagram for explaining the
`intensity of transmitted light of the embodiment of FIG. 20;
`FIG. 23A is a sectional view showing an embodiment of
`a light reflecting layer for use with the edge-light type
`surface light source;
`FIG. 23B is a sectional view showing an embodiment of
`a light reflecting layer for use with the edge-light type
`surface light source;
`FIG. 23C is a sectional view showing an embodiment of
`a light reflecting layer for use with the edge-light type
`surface light source;
`FIG. 23D is a sectional view showing an embodiment of
`a light reflecting layer for use with the edge-light type
`surface light source;
`FIG. 23E is a sectional view showing an embodiment of
`a light reflecting layer for use with the edge-light type
`surface light source;
`FIG. 24A is a perspective view showing a first embodi(cid:173)
`ment of a lenticular lens according to a second invention;
`FIG. 24B is a perspective view showing a first embodi(cid:173)
`ment of a lenticular lens according to a second invention;
`
`4
`FIG. 25 is a sectional view showing a second embodiment
`of the lenticular lens according to the second invention;
`FIG. 26A is a sectional view showing the shape of
`concave lens elements of the lenticular lens according to an
`5 embodiment of the second invention;
`FIG. 26B is a sectional view showing the shape of
`concave lens elements of the lenticular lens according to an
`embodiment of the second invention;
`FIG. 26C is a sectional view showing the shape of
`10 concave lens elements of the lenticular lens according to an
`embodiment of the second invention;
`FIG. 27 is a schematic diagram showing optical paths of
`rays of light transmitted through a lenticular lens according
`to an embodiment of the second invention;
`FIG. 28 is a schematic diagram showing optical paths of
`rays of light transmitted through a lenticular lens according
`to an embodiment of the second invention;
`FIG. 29 is a schematic diagram showing optical paths of
`rays of light transmitted through a lenticular lens according
`to an embodiment of the second invention;
`FIG. 30 is a schematic diagram showing optical paths of
`rays of light transmitted through a lenticular lens according
`to an embodiment of the second invention;
`FIG. 31 is a graph showing transmission characteristics of
`the lenticular lens according to the second invention;
`FIG. 32A is a sectional view showing a composition of a
`lenticular lens and a light isotopic diffusing layer according
`to an embodiment of the second invention;
`FIG. 32B is a sectional view showing a composition of a
`lenticular lens and a light isotopic diffusing layer according
`to an embodiment of the second invention;
`FIG. 33A is a sectional view showing a composition of a
`lenticular lens and a light isotopic diffusing layer according
`to an embodiment of the second invention;
`FIG. 33B is a sectional view showing a composition of a
`lenticular lens and a light isotopic diffusing layer according
`to an embodiment of the second invention;
`FIG. 34 is a sectional view showing a first embodiment
`40 (back-light type) of a surface light source according to the
`second invention;
`FIG. 35 is an exploded perspective view showing a
`second embodiment (edge-light type) of the surface light
`source according to the second invention;
`FIG. 35A is a detailed drawing of the isotopic diffusing
`layer of the surface light source of FIG. 35;
`FIG. 35B is a detailed drawing of the lenticular lens of the
`surface light source of FIG. 35.
`FIG. 36A is a sectional view for explaining characteristics
`of the light guiding plate of FIG. 25;
`FIG. 36B is a sectional view for explaining characteristics
`of the light guiding plate of FIG. 25;
`FIG. 36C is a sectional view for explaining characteristics
`55 of the light guiding plate of FIG. 25;
`FIG. 37 is a perspective view showing an embodiment of
`an edge-light type surface light source and a transmission
`type display apparatus having the surface light source
`according to a third invention;
`FIG. 38 is a perspective view showing an embodiment of
`a back-light type surface light source and a transmission
`type display apparatus having the surface light source
`according to the third invention;
`FIG. 39A is a perspective view showing an embodiment
`(convex elliptic cylinder lenticular lens) of a lens sheet
`according to the third invention;
`
`45
`
`50
`
`60
`
`65
`
`Page 50 of 82
`
`

`

`5,592,332
`
`25
`
`6
`FIG. 50 is a sectional view for explaining that part of rays
`of light which outwardly travels from a light guiding plate
`is totally reflected by a lens sheet according to the third
`invention and that the rest of the rays oflight are transmitted;
`FIG. 51 is a sectional view showing a first embodiment of
`a fabrication method according to the third embodiment;
`FIG. 52 is a graph showing the characteristics of a second
`embodiment of the edge-light type surface light source
`according to the third invention, the graph illustrating an
`angle distribution of the intensity of emitted light of a
`convex elliptic cylinder lenticular lens whose longer axis
`accords with a normal direction thereof;
`FIG. 53 is a graph showing the characteristics of an
`edge-light type surface light source according to a first
`comparison example, the graph illustrating an angle distri(cid:173)
`bution of the intensity of emitted light of a triangular
`cylinder lenticular lens;
`FIG. 54 is a graph showing the characteristics of an
`edge-light type surface light source according to a second
`comparison example, the graph illustrating an angle distri(cid:173)
`bution of the intensity of emitted light of a convex elliptic
`cylinder lenticular lens whose shorter axis accords with a
`normal direction thereof;
`FIG. 55 is a graph showing the characteristics of an
`edge-light type surface light source according to a third
`comparison example, the graph illustrating an angle distri(cid:173)
`bution of the intensity of emitted light of the surface light
`source, the surface light source having two light diffusing
`layers (films) layered over a light guiding plate;
`FIG. 56A and FIG. 56C are a schematic diagram showing
`the position of total reflection critical point Pc and optical
`paths of rays of light of a lenticular lens according to the
`fourth invention and a characteristic graph relating to FIG.
`35 56A, respectively;
`FIG. 56B and FIG. 56D are a schematic diagram showing
`the optical paths of rays of light of a lenticular lens with a
`large cutting depth D and a total reflection critical point Pc
`and a characteristic graph relating to FIG. 56B, respectively;
`FIG. 57 A is a schematic diagram showing the optical
`paths of diffused rays of light entered into a lenticular lens
`according to the fourth invention;
`FIG. 57B is a schematic diagram showing the optical
`45 paths of diffused rays of light entered into a lenticular lens
`with a large cutting depth D and a total reflection critical
`point Pc; and
`·
`FIG. 58 is a graph showing the characteristics of an
`edge-light type surface light source according to a fourth
`comparison example, two delustered transparent sheets
`being disposed on a light emitting surface of a light guiding
`plate.
`
`5
`FIG. 39B is a perspective view showing an embodiment
`(concave elliptic cylinder lenticular lens) of the lens sheet
`according to the third invention;
`FIG. 39C is a perspective view showing an embodiment
`(convex elliptic cylinder lenticular lens) of the lens sheet 5
`according to the third invention;
`FIG. 39D is a perspective view showing an embodiment
`(concave elliptic cylinder lenticular lens) of the lens sheet
`according to the third invention;
`FIG. 40A is a sectional view for explaining optical paths 10
`in a lens sheet, particularly, a spherical aberration of a
`convex perfect cylinder lens element according to the third
`invention;
`FIG. 40B is a sectional view for explaining optical paths,
`in a lens sheet, particularly, a spherical aberration of a 15
`convex elliptic cylinder lens element according to the third
`invention;
`FIG. 41A is a sectional view for explaining optical paths
`in a lens sheet, particularly, a spherical aberration of a
`concave perfect cylinder lens element according to the third 20
`invention;
`FIG. 41B is a sectional view for explaining optical paths,
`in a lens sheet, particularly, a spherical aberration of a
`concave elliptic cylinder lens element according to the third
`invention;
`FIG. 42A is a perspective view showing another embodi(cid:173)
`ment of the lens s